Accession Number:

ADA210281

Title:

Electromagnetic Induction Remote Sensing of Sea Ice Thickness. Phase 1

Descriptive Note:

Final rept. 1 Jan-31 Aug 1986

Corporate Author:

FLOW RESEARCH CO KENT WA TECHNOLOGY DIV

Personal Author(s):

Report Date:

1986-09-22

Pagination or Media Count:

46.0

Abstract:

This report documents an investigation of the utility of electromagnetic EM induction as a technique for measuring sea ice thickness. A computer code was used to calculate the theoretical response of an existing EM induction geophysical tool, the Geonics Ltd. EM-31D, to sea ice thickness. The code also was used to evaluate the expected effect on the thickness measurements of ice conductivity, seawater conductivity, instrument height, and water depth. The instrument was taken to the Artic Ocean to test its actual response to ice thickness, including the effect of coils orientation, and instrument height. The measurements made by the instrument generally corresponded well with theory. Correspondence for the vertical coplanar coils configuration was better than for horizontal coils configuration. For the ice thickness tested, 0.10, 0.85 and 1. 68 m, the instrument output for vertical coils deviated from physical measurements by an average of 0.06 meters. Even greater accuracy would be possible if on-ice calibration procedures were developed. It is concluded that EM induction offers a practical and rapid method of measuring sea ice thickness. Modifications to the instrument to allow real time ice thickness and water conductivity readouts are described. The application of this technology to air-droppable buoys is discussed.

Subject Categories:

  • Snow, Ice and Permafrost
  • Electrical and Electronic Equipment
  • Computer Programming and Software
  • Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE